What's with DL's flight schedules these days? I've been trying to book MSP-GCM and with the exception of one flight, the rest of the itineraries have 12+ hour layovers in ATL. I don't understand why. Of course the only flight with a reasonable layover is a K fare, so does it really boil down to revenue? How does a 12 - 18 or more hour layover improve DL revenue?